@misc{indiciae37ac5a2522c6,
  title = {Simple formula for the atomic forces in the augmented-plane-wave method.},
  author = {JM Soler and AR Williams},
  year = {1989},
  doi = {10.1103/physrevb.40.1560},
  url = {https://pubmed.ncbi.nlm.nih.gov/9992009/},
  note = {Source identifier: 9992009}
}